Cytogenetic abnormalities and reproductive failures

Abnormal reproductive outcomes, also defined as "reproductive failures" include a wide variety of problems as: infertility, pregnancy loss, abnormal pregnancy, birth defects, and childhood cancer. The cause of almost any reproductive abnormality can be the result of genetic and physiological events that occurred in mother, father and child. Among reproductive failures causes, chromosomal changes are encountered quite frequently. In order to identify the cytogenetic causes potentially involved in the reproductive failures, we investigated 128 persons. From this, 102 were individual persons or partners in infertile couples, and the other 26 cases were members of 9 different families. Short term cell cultures from peripheral blood, cell-cycle synchronization, standard methods for cytogenetic slides, conventional GTG and CBG banding techniques have been used for cytogenetic investigations. Numerical and structural aberrations were identified in 14.7% of cases. Aneuploidy of sex chromosomes, deletion of short arms of Y and X chromosomes was identified mostly in mosaic form. In 5% of cases with spontaneous abortions pericentric inversion inv(9)(p12q13), was identified. A Robertsonian translocation t(13;14) was found in a Prader-Willi boy who inherited the cytogenetic abnormality from his healthy mother. Balanced inherited rearrangements were found in 5 families, maternally transmitted in 3 families, and of paternal origin in 2 families. Overall, 8 cases with normal phenotype proved to be carriers of balanced rearrangements. Our results underline the importance of cytogenetic investigation in all instances of reproductive failures, to offer a well informed genetic counseling and improve the management of these cases.